Michael Barone‘s latest number-crunching exercise for the Washington Examiner yields some good news for Republicans:

Republicans snatched control of about 20 legislative houses from Democrats. And by margins that hardly any political insiders expected. Republicans needed five seats for a majority in the Pennsylvania House and won 15; they needed four seats in the Ohio House and got 13; they needed 13 in the Michigan House and got 20; they needed two in the Wisconsin Senate and four in the Wisconsin House and gained four and 14; they needed five in the North Carolina Senate and nine in the North Carolina House and gained 11 and 15.

All those gains are hugely significant in redistricting. When the 2010 Census results are announced next month, the 435 House seats will be reapportioned to the states, and state officials will draw new district lines in each state. A nonpartisan commissions authorized by voters this year will do the job in (Democratic) California, but in most states it’s up to legislators and governors (although North Carolina’s governor cannot veto redistricting bills).

Republicans look to have a bigger advantage in this redistricting cycle they’ve ever had before. It appears that in the states that will have more than five districts (you can make only limited partisan difference in smaller states) Republicans will control redistricting in 13 states with a total of 165 House districts and Democrats will have control in only four states with a total of 40 districts. You can add Minnesota (seven or eight districts) to the first list if the final count gives Republicans the governorship and New York (27 or 28 districts) to the second list if the final count gives Democrats the state Senate.